Washing machine with vibration isolation system

ABSTRACT

A vibration isolation system for a front-loading clothes washing machine and the like which provides isolation of intermittent or continuous vibration of a rotating basket from support feet which support the washing machine. The vibration isolation system includes a plurality of vibration isolation assemblies each including a flexible member or rod which is supported by a pair of opposing bearing supports. The vibration assemblies can be located between a cabinet enclosing the basket and the support feet, a drum generally enclosing the basket and the cabinet, or any other suitable location between the basket and the support feet. The configuration of the flexible members relative to one another and the spinning axis of the basket may vary depending upon the design of the washing machine components.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of U.S. Provisional Patent Application No. 61/367,037 filed on Jul. 23, 2010, the disclosure of which is expressly incorporated herein in its entirety by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not applicable

PARTIES TO A JOINT RESEARCH AGREEMENT

Not applicable

REFERENCE TO APPENDIX

Not applicable

FIELD OF THE INVENTION

The field of the present invention generally relates to systems and methods for isolating vibration originating from an object and, more particularly, to an isolation system and method for machines for industrial or consumer use including but not limited to clothes washing machines.

BACKGROUND OF THE INVENTION

The operation of conventional front-loading clothes washing machines frequently results in undesirable vibration and/or noise. User response to this vibration and/or noise may range from minor annoyance to major aggravation.

Noise and vibration problems may be exacerbated when the clothes washing machines are placed in locations close to living or sleeping areas; noise or vibration from a first floor laundry room is more likely to disrupt conversations, television watching, or the like in other first floor rooms than noise or vibration from a basement laundry room. Similarly, noise or vibration from a bedroom level laundry room (such as the recently popular second floor laundry room) is more likely to disrupt sleep than noise from a laundry room located on a different level. Noise and vibration problems also may originate from clothes washing machines operated by others when individuals work or reside in close proximity to others, as is frequently the case in urban environments and attached residences.

Noise and vibration problems also may be exacerbated when clothes washing machines are installed in locations that tend to transmit rather than disperse vibration. Washing machines on upper building floors (i.e., not on a basement or slab floor) may readily transmit noise and vibration throughout the building and its contents.

Excessive vibration also may cause disruption or damage in addition to adversely affecting user comfort. Excessive vibration may result in movement of the clothes washing machine relative to the support surface, which in turn may cause problems including disruption of machine operation or physical damage to the machine or its environment. Movement of the clothes washing machine relative to its support can disrupt machine operation, mark or tear finished flooring, or cause water damage if a water supply hose is damaged or disconnected. Forces associated with the rotating shafts of clothes washing machines also may cause damaging movement or vibration of structures in the machine that support the shafts and retain them in position.

Manufacturers of conventional front-loading clothes washing machines have endeavored to produce quieter units but have not consistently achieved success. These machines typically comprise a steel cabinet into which is mounted a clothes basket enclosed in a steel or polymer housing or tub. This housing is isolated from the steel cabinet by one or more isolation mechanisms such as springs, dampers, and elastomers which collectively comprise the isolation system. The drive system typically comprises a variable speed motor mounted to the housing and connected to a larger flywheel on the basket driveshaft through a belt. In some instances, the motor is connected directly to the basket driveshaft. FIG. 1 schematically shows a typical factory-installed isolation system comprising two springs supporting the clothes basket housing and extending from the top of the clothes washing machine cabinet to each side of the housing and four dampers extending from the from the bottom surface of the housing to the bottom of the cabinet.

Despite the presence of isolation systems in prior front-loading clothes washing machines, operation of these machines can still cause undesirable vibration and/or noise. In addition, clothes washing machines that exhibit satisfactory performance in an idealized test situation may nevertheless cause undesirable noise and vibration if they are located in an environment that does not allow the vibration to dissipate. Conventional external damping methods such as placement of elastomeric or similar pads under the clothes washing machine also have had only limited success. Although various solutions to this problem have been proposed, none to date has provided a reliable and inexpensive solution. Accordingly, a need exists for an effective vibration isolation system for front-loading clothes washing machines and the like.

SUMMARY OF THE INVENTION

The present invention provides an isolation system and method which addresses at least one of the above-noted problems of the related art. Disclosed is a front-loading washing machine comprising, in combination, a frame, a plurality of support feet for supporting the frame, a drum supported within the frame, a basket within the drum and rotatable about a substantially horizontal central axis, and a vibration isolation system including a plurality of vibration isolation assemblies mounted between the frame and the support feet. Each vibration isolation assembly includes a flexible member having opposed end portions and a central portion intermediate the end portions, and a pair of opposed bearing supports supporting the flexible member at the flexible member end portions, and a connector secured to the central portion of the elastic member.

Also disclosed is a front-loading washing machine comprising, in combination, a frame, a drum supported within the frame, a basket within the drum and rotatable about a substantially horizontal central axis, and a vibration isolation system including a plurality of vibration isolation assemblies mounted between the drum and the frame. Each vibration isolation assembly includes an elastic member having opposed end portions and a central portion intermediate the end portions, a pair of opposed bearing supports supporting the elastic member at the elastic member end portions, and a connector secured to the central portion of the elastic member.

From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of vibration isolation systems. Particularly, significant in this regard is the potential the invention affords for providing a reliable, inexpensive, and effective vibration isolation system for front-loading washing machines. Additional features and advantages of the invention will be better understood in view of the detailed description provided below.

BRIEF DESCRIPTION OF THE DRAWINGS

These and further features of the invention will be apparent with reference to the following description and drawings.

FIG. 1 shows front schematic view of a conventional front-loading clothes washing machine.

FIG. 2 shows side schematic view of a conventional front-loading clothes washing machine.

FIG. 3 shows rear schematic view of a conventional front-loading clothes washing machine.

FIG. 4 shows front schematic view of a front-loading clothes washing machine according to a first embodiment of the present invention.

FIG. 5 shows side schematic view of the front-loading clothes washing machine of FIG. 4.

FIG. 6 shows rear schematic view of the front-loading clothes washing machine of FIGS. 4 and 5.

FIG. 7 is a top perspective view of a base plate of the front-loading clothes washing machine of FIGS. 4 to 6 showing a plurality of vibration isolation assemblies secured thereto.

FIG. 8 is a bottom perspective view of the base plate of FIG. 7.

FIG. 9 is a side elevational view of the base plate of FIGS. 7 and 8.

FIG. 10 is a top plan view of the base plate of FIGS. 7 to 9.

FIG. 11 is a top perspective view of a vibration isolation assembly secured to the base plate of FIGS. 7 to 9.

FIG. 12 is a top plan view of the vibration isolation assembly of FIG. 11.

FIG. 13 is a side elevational view of the vibration isolation assembly of FIGS. 11 and 12.

FIG. 14 shows a front schematic view of a front-loading clothes washing machine according to a second embodiment of the present invention, wherein two vibration isolation assemblies arranged parallel to the spinning axis of the basket.

FIG. 15 shows a side schematic view of the front-loading clothes washing machine of FIG. 14.

FIG. 16 shows a rear schematic view of the front-loading clothes washing machine of FIGS. 14 and 15.

FIG. 17 shows a front schematic view of a front-loading clothes washing machine according to a third embodiment of the present invention, wherein three vibration isolation assemblies are arranged parallel to the spinning axis of the basket.

FIG. 18 shows a side schematic view of the front-loading clothes washing machine of FIG. 17.

FIG. 19 shows a rear schematic view of the front-loading clothes washing machine of FIGS. 17 and 18.

FIG. 20 shows a front schematic view of a front-loading clothes washing machine according to a fourth embodiment of the present invention, wherein four vibration isolation assemblies are arranged parallel to the spinning axis of the basket.

FIG. 21 shows a side schematic view of the front-loading clothes washing machine of FIG. 20.

FIG. 22 shows a rear schematic view of the front-loading clothes washing machine of FIGS. 20 and 21.

FIG. 23 shows a front schematic view of a front-loading clothes washing machine according to a fifth embodiment of the present invention, wherein two vibration isolation assemblies are arranged perpendicular to the spinning axis of the basket.

FIG. 24 shows a side schematic view of the front-loading clothes washing machine of FIG. 23.

FIG. 25 shows a rear schematic view of the front-loading clothes washing machine of FIGS. 23 and 24.

FIG. 26 shows a front schematic view of a front loading clothes washing machine according to a sixth embodiment of the present invention, wherein four vibration isolation assemblies arranged parallel to the spinning axis of the basket and wherein energy damping devices are positioned between the vibration isolation assemblies and the drum.

FIG. 27 shows a side schematic view of the front-loading clothes washing machine of FIG. 26.

FIG. 28 shows a rear schematic view of the front-loading clothes washing machine of FIGS. 26 and 27.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the various machines as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the clothes washing machines illustrated in the drawings. In general, up or upward generally refers to an upward direction within the plane of the paper in FIG. 4 and down or downward generally refers to a downward direction within the plane of the paper in FIGS. 4 and 11. Also in general, fore or forward generally refers to a direction out of the plane of the paper in FIG. 2 and aft or rearward generally refers to a direction into the plane of the paper in FIG.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the vibration isolation system disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with reference to a front-loading or horizontal axis clothes washing machine. Other embodiments suitable for other applications will be apparent to those skilled in the art given the benefit of this disclosure.

The present invention comprises a vibration isolation system for a front-loading clothes washing machine which isolates support feet of the clothes washing machine from the vibration source using a plurality of knife-edge support isolators (KESI) units or vibration isolation assemblies so that vibration is not transferred to the floor or other support surface upon which the clothes washing machine is supported. The vibration isolation system is effective in isolating continuous or intermittent vibration. Clothes washing machines with the vibration isolation system of the present invention offer superior vibration isolation compared to clothes washing machines having conventional vibration isolation systems.

The illustrated vibration isolation system of the present invention can connect the support feet to a cabinet or frame using the vibration isolation assemblies. Each illustrated vibration isolation assembly includes an elongate elastic member or rod having end portions supported by a pair of spaced-apart knife-edge supports or bearing supports and capable of bending in response to load applied to a central or mid portion of the elastic member intermediate the pair of bearing supports to allow oscillation of the elastic member in response to vibrating load in communication with the elastic member, and a connector for operably connecting the mid portion of the elastic member. The elastic member is capable of deflecting from an original position to a more or less bowed position in response to changes in load in communication with the mid portion of the elastic member intermediate its end portions, with the amount of deflection being dependent on the magnitude of the applied force within the load bearing capacity of the elastic member. The elastic member is also capable of returning to its original position when the original force acting on the elastic member is restored. See U.S. Pat. Nos. 6,220,563, 6,595,483, and 7,086,509, the disclosures of which are expressly incorporated herein in their entireties by reference, for examples of possible variations of the vibration isolator assemblies. The bearing supports may be operably connected to the frame with the connector operably connected to the support feet. Alternatively, the bearing supports may be operably connected to the support feet with connector operably connected to the frame.

The illustrated elastic members have opposing end portions and a central portion intermediate the end portions. The bearing supports may be any suitable supports that both engage the elastic member end portions and limit movement of the elastic members only in a longitudinal direction (i.e., along the long axis of the elastic member). The elastic members are freely moveable relative to the bearing supports in response to vibration or other forces except in the longitudinal direction. Suitable supports may include spherical joint rod ends, spherical joint bearings, and other conventional supports. Longitudinal motion of the elastic member end portions may be restricted by collars provided on the elastic members or in any other suitable manner.

The elastic member may comprise any suitable material which allows it to deflect in response to changes in the applied load and return essentially to its original position when the original load is restored including but not limited to pultruded fiberglass-reinforced epoxy. The material of the elastic member alternatively can be metal, plastic, elastomer, composite materials, or any other suitable material. The elastic member should be selected to have a static deflection appropriate for the anticipated load, with greater static deflection being required to isolate lower frequency vibrations. The illustrated elastic member is a unitary member of solid round cross-section but any suitable shape can be utilized, including but not limited to hollow tubes, I-beams, or the like. The elastic member can alternatively be a composite member comprising a bundle of continuous elastic subunits held together by any suitable means.

The elastic members may be located at any location as dictated by the design of the clothes washing machine. The r elastic members may be mounted in any orientation with respect to the spinning axis of the clothes washing machine basket, including perpendicular, parallel, or at other angles as dictated by the design of the clothes washing machine. The bearing supports may be arranged such that the elastic members are positioned to support the load supported on them and respond to the expected vibration frequencies. Any configuration of two or more elastic members (other than a collinear two-elastic members arrangement) may be used.

Undesirable vibration resulting from operation of a front-loading clothes washing machine may occur primarily over a narrow frequency range or may vary over a broad frequency range during the operating cycle depending on the design of the clothes washing machine. It is anticipated that vibration frequencies for at least some applications will be within a narrow enough range and that the vibration isolation assemblies may be configured to accommodate this range of vibration frequencies without adjustment. Vibration isolation assemblies intended for use over a narrow vibration frequency range may be passive, with the bearing supports provided at fixed locations. In these passive vibration isolation assemblies, each of the elastic members has a corresponding fixed length selected (tuned) for optimal performance at the frequency to be isolated (e.g., the high or low level spin speed of the clothes washing machine). The distance between opposing pairs of bearing supports need not be equal but an equidistant arrangement may improve the performance of the vibration isolation system.

Active vibration isolation systems intended for use over a broader vibration frequency may be tuned to the resonant frequency or frequencies of interest using an adjustment mechanism. This may be accomplished by changing the distance between the respective bearing supports on which the elastic members is supported. The adjustment mechanism may be any suitable adjustment mechanism including, without limitation, a continuously adjustable threaded rod that changes the distance between the pairs of bearing supports. Active vibration isolation systems may be capable of sensing the rotational speed of the basket inside of the housing or drum and adjusting the distance between the pair of opposing bearing supports to best match this rotational speed. The adjustment mechanism may be controlled by an automated device such as a microprocessor that monitors the vibration frequency, compares it to a standard value, and changes the effective stiffness of at least one elastic members by adjusting the distance between the pair of opposing bearing supports. For example see U.S. Pat. No. 7,086,509, the disclosure of which is expressly incorporated herein in its entirety by reference.

FIGS. 4 to 6 illustrate a front-loading clothes washing machine 10 according to a first embodiment of the present invention. The illustrated clothes washing machine 10 includes a cabinet or frame 12 having a base plate 14 at the bottom thereof, and a plurality of support feet 16 extending below the base plate 14 for supporting the frame 12 on a support surface such as a floor, a pedestal, a clothes dryer, and the like. Within the frame 12 is a basket housing or drum 18 which houses a clothes basket 20, which rotates about a horizontal central axis of rotation 22, within the basket housing 18. An illustrated drive system for the clothes basket 20 includes an electric drive motor 24 secured to the drum 18, a drive pulley 26 secured to the rear end of the closed basket 20 outside the basket housing 18, and a drive belt 28 operably connecting an output shaft of the drive motor 24 with the drive pulley 26 of the clothes basket 20 so that rotation of the motor output shaft in either direction rotates the clothes basket 20 within the drum 18. It is noted that any other suitable type of drive system can alternatively be utilized. The illustrated clothes washing machine 10 also includes a drum isolation system 30 a and a vibration isolation system 30 b.

The illustrated drum isolation system 30 a comprises a plurality of springs 32 extending from the top of the frame 12 to each side of the drum 18 to support the drum 18 within the frame 12 and a plurality of dampers 34 extending from the from the bottom of the drum 18 to the base plate 14 of the frame 12. The coil springs 32 can be of any suitable type as known in the industry. The dampers 34 can be of any suitable type as known in the industry. The illustrated drum isolation system 30 a includes two of the springs 32 and four of the dampers 34 but it is noted that any other suitable quantities can alternatively be utilized. It is also noted that any other suitable type of drum isolation system 30 a can alternatively be utilized.

As best shown in FIGS. 7 to 10, the illustrated vibration isolation system 30 b comprises a plurality of vibration isolation assemblies 36 located between the base plate 14 of the frame 12 and the support feet 16. The illustrated vibration isolation system 30 b includes four of the vibration isolation assemblies 36 wherein there is a single vibration isolation assembly 36 associated with each of the four support feet 16 but it is noted that any other suitable quantity of vibration isolation assemblies 36 can alternatively be utilized. For example, each vibration isolation assembly 36 can alternatively be associated with two of the support feet 16 so that two of the vibration isolation assemblies 36 are used with the four support feet 16. The illustrated vibration isolation assemblies 36 are each arranged parallel to the horizontal central axis 22 of the clothes basket 20.

As best shown in FIGS. 11 to 13, the illustrated vibration isolation assemblies 36 can each comprise an elongate elastic member or rod 38, opposing knife-edge supports or bearing supports 40 supporting end portions of the elastic member 38, and a connector 42 operably connecting a central portion of the elastic member 38 intermediate the bearing supports 40 to the support foot 16. The bearing supports 40 may be of any suitable type such as, for example, spherical joint rod ends, spherical joint bearings, other conventional supports, or the like. The illustrated bearing supports 40 are formed by spherical-joint rod ends having a threaded shaft and a pair of nuts 43 which enable the bearing supports 40 to be secured in openings at fixed positions in the base plate 14. It is noted that the bearing supports 40 can alternatively be secured to base plate 14 in any other suitable manner. The illustrated elastic member 38 is provided with collars 44 secured at fixed positions on the elastic member 38 to limit outward longitudinal motion of the elastic member end portions relative to the bearing supports 40. It is noted that the illustrated collars 44 do not limit inward longitudinal movement of the elastic member end portions relative to the bearing supports 40 as the elastic member 38 flexes. The connector 42 may be of any suitable type such as, for example, spherical joint rod ends, spherical joint bearings, other conventional connectors, or the like. The illustrated connector 42 is formed by a spherical joint rod end having a pair collars 44 secured at opposed fixed positions on the elastic member 38 to prevent longitudinal motion of the elastic member 38 relative to the connector 42 and a threaded shaft secured to the support foot 16. It is noted that the connector 42 can alternatively be secured to elastic member 38 and/or the support foot 16 in any other suitable manner.

If desired, springs may be provided on opposing ends of the elastic member 38 between the bearing supports 40 and the corresponding end portions of the elastic member 38. This may be accomplished, for example, by providing connecting the spring to the end of the elastic member 38 or providing a shaft collar on the end of the elastic member 38 to retain the spring between the shaft collar and the bearing support 40. Compression of the spring increases a vector component of friction on the elastic member 38 and decreases its effective static deflection. Evidence suggests that this may improve system performance through resonance.

As best shown in FIGS. 7 to 10, the illustrated knife edge supports 40 are secured to the base plate 14 and extend upwardly from the base plate 14 to support the elastic members 38 within the frame. The connectors 42 extend downwardly from the elastic members 38 to the support feet 16 located below the base plate 14. Clearance openings 45 are provided in the base plate 14 to permit relative motion between the base plate 14 and the support feet 16 as the elastic members 38 deflect.

The vibration isolation system 10 can alternatively be positioned between the drum 18 and the cabinet or frame 12 to isolate the support feet 16 from the vibration source. The vibration isolation system 10 can connect the drum 18 to the frame 12 using a plurality of the vibration isolation assemblies 36. The bearing supports 40 may be operably connected to the frame 12 with the connectors 42 operably connected to the drum 18. Alternatively, the bearing supports 40 may be operably connected to the drum 18 with the connectors 42 operably connected to the frame 12.

The elastic members 38 may be located on any side of the drum 18 as dictated by the design of the clothes washing machine 10. The elastic members 38 may be mounted in any orientation with respect to the spinning axis 22 of the clothes washing machine basket 18, including perpendicular, parallel, or at other angles as dictated by the design of the clothes washing machine 10. The bearing supports 40 may be arranged such that the elastic members are positioned to support the load supported on them and respond to the expected vibration frequencies. Any configuration of two or more elastic members 38 (other than a collinear two-elastic member arrangement) may be used.

FIGS. 14 to 16 illustrate clothes washing machine according to a second embodiment of the invention. Two of the vibration isolation assemblies 30 are arranged parallel to the spinning axis 22 of basket 20. The illustrated elastic members 38 extend in a horizontal forward rearward direction and are located on opposed lateral sides of the drum 18. The illustrated elastic members 38 extend a length about equal to the length of the drum 18 but any other suitable length can alternatively be utilized. The illustrated elastic members 30 are located at a height substantially equal to the spinning axis 22 of the basket 20. The illustrated bearing supports 40 are secured to the frame 12 with the connectors 42 secured to the drum 18. Alternatively, the bearing supports 40 may secured to the drum 18 with the connectors 42 secured to the frame 12. It is noted that alternatively any other suitable quantity and/or locations of the elastic members 38 can be alternatively utilized.

FIGS. 17 to 19 illustrate a clothes washing machine according 10 to a third embodiment of the present invention. Three of the vibration isolation assemblies 36 are arranged parallel to the spinning axis 22 of basket 20. The illustrated elastic members 38 extend in a horizontal forward rearward direction. Two of the elastic members 38 are located on opposed lateral sides of the drum 18 near the bottom of the drum 18 and the other elastic member 36 is centrally located above the drum 18 and above the spinning axis 22 of the basket 20. The illustrated elastic members 38 extend a length about equal to the length of the drum 18 but any other suitable length can alternatively be utilized. The illustrated bearing supports 40 are secured to the drum 18 with the connectors 42 secured to the frame 12. Alternatively, the bearing supports 40 may be secured to the frame 12 with the connectors 42 secured to the drum 18. It is noted that alternatively any other suitable quantity and/or locations of the elastic members 38 can be alternatively utilized.

FIGS. 20 to 22 illustrate a clothes washing machine 10 according to a fourth embodiment of the present invention. Four of the vibration isolation assemblies 36 are arranged parallel to the spinning axis 22 of the basket 20. The illustrated elastic members 38 extend in a horizontal forward rearward direction and are located below the drum 18. Pairs of the elastic members 36 are located in a side-by side manner near opposed lateral sides of the drum 18. The illustrated elastic members 38 extend a length about equal to the length of the drum 18 but any other suitable length can alternatively be utilized. The illustrated elastic members 30 are located at a height near the bottom of the drum 18. The illustrated base plate 14 of the frame 12 is extend upward to accommodate attachment of the vibration isolation assemblies 36 thereto. A spacer of extension of any suitable type can be utilized. The illustrated bearing supports 40 are secured to the base plate 14 of frame 12 with the connectors 42 secured to the drum 18. Alternatively, the bearing supports 40 may secured to the drum 18 with the connectors 42 secured to the base plate 14 of the frame 12. It is noted that alternatively any other suitable quantity and/or locations of the elastic members 38 can be alternatively utilized.

FIGS. 23 to 25 illustrated a clothes washing machine 10 according to fifth embodiment of the present invention. Two of the vibration isolation assemblies 36 are arranged perpendicular to the spinning axis 22 of the basket 20. The illustrated elastic members 38 extend in a vertical upward/downward direction and are located on opposed lateral sides of the drum 18. The illustrated elastic members 38 extend a length about equal to the height of the drum 18 but any other suitable length can alternatively be utilized. The illustrated elastic members 30 are centrally located at the middle of the length of the drum 18. The illustrated bearing supports 40 are secured to the frame 12 with the connectors 42 secured to the drum 18. Alternatively, the bearing supports 40 may secured to the drum 18 with the connectors 42 secured to the frame 12. It is noted that alternatively any other suitable quantity and/or locations of the elastic members 38 can be alternatively utilized.

FIGS. 26 to 25 illustrate a clothes washing machine 10 according to a sixth embodiment of the present invention. Four of the vibration isolation assemblies 36 are arranged parallel to the spinning axis 22 of the basket 20. The illustrated elastic members 38 extend in a horizontal forward rearward direction and are located below the drum 18. Pairs of the illustrated elastic members 36 are substantially coaxial and located near opposed lateral sides of the drum 18. The illustrated elastic members 38 extend a length about equal to half the length of the drum 18 but any other suitable length can alternatively be utilized. The illustrated elastic members 30 are located at a height near the base plate 14 of the frame. Dampers 34 are provided between the vibration isolation assemblies 36 and the bottom of the drum 18. The dampers 34 can be of any suitable type known in the industry. A pair of coiled springs 32 extend from the frame 12 to the top of the drum 18 on opposed sides of the drum 18 and centrally along the length of the drum 18. The coiled springs 32 can be of any suitable type known in the industry to return the dampers 40 to a neutral extension, or alternatively other types of springs or additional vibration isolation assemblies can be utilized. It is noted that any other suitable quantity of the coiled springs 32 can alternatively be utilized. The illustrated bearing supports 40 are secured to the base plate 14 of frame 12 with the connectors 42 secured to the bottom of the dampers 34 whose upper ends are secured to the drum 18. Alternatively, the bearing supports 40 may secured to the bottom of the dampers 34 whose upper ends are secured to the drum 18 with the connectors 42 secured to the base plate 14 of the frame 12. It is noted that alternatively any other suitable quantity and/or locations of the coiled springs 32, the dampers 34, and/or the elastic members 38 can be alternatively utilized.

It is noted that the vibration isolation assemblies can alternatively be located in any other suitable location in order to isolate the base plate 14 and/or support feet 16 from the vibration source. For example, without limitation, the base plate 14 can be formed as a separate component from the remainder of the frame 12 and the vibration isolation assemblies can be located between the base plate 14 and the remainder of the frame 12.

Any of the features or attributes of the above described embodiments and variations can be used in combination with any of the other features and attributes of the above described embodiments and variations as desired.

From the foregoing disclosure and detailed description of certain preferred embodiments, it is also apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled. 

1. A front-loading washing machine comprising, in combination: a frame; a plurality of support feet for supporting the frame; a drum supported within the frame; a basket within the drum and rotatable about a substantially horizontal central axis; a vibration isolation system including a plurality of vibration isolation assemblies mounted between the frame and the support feet; and each vibration isolation assembly including a flexible member having opposed end portions and a central portion intermediate the end portions, and a pair of opposed bearing supports supporting the flexible member at the flexible member end portions, and a connector secured to the central portion of the elastic member.
 2. The front-loading washing machine of claim 1, wherein a distance between the bearing supports is fixed based on the operating frequency of the basket.
 3. The front-loading washing machine of claim 2, wherein a length of the elastic member is selected to correspond to the fixed distance between the bearing supports.
 4. The front-loading washing machine of claim 1, wherein at least two of the elastic members are arranged in substantially parallel relationship.
 5. The front-loading washing machine of claim 1, wherein the elastic members are arranged in substantially parallel relationship to the horizontal central axis of the basket.
 6. The front-loading washing machine of claim 1, wherein a distance between the respective bearing supports can be adjusted automatically based on an operational frequency of the washing machine.
 7. The front-loading washing machine of claim 1, further comprising an adjustment system for changing a distance between the respective bearing supports automatically based on an operational frequency of the washing machine.
 8. The front-loading washing machine of claim 1, further comprising a mechanism for adjusting the resonant frequency of the elastic member and the respective bearing supports.
 9. The front-loading washing machine of claim 8, wherein the adjustment mechanism changes a distance between the respective bearing supports.
 10. The front-loading washing machine of claim 9, wherein the adjustment mechanism comprises a continuously adjustable threaded rod that changes the distance between the respective bearing supports.
 11. The front-loading washing machine of claim 9, wherein the adjustment mechanism comprises an automated system for monitoring the vibration frequency, comparing it to a standard value, and changing the distance between the respective bearing supports in response to this comparison.
 12. The front-loading washing machine of claim 1, wherein the bearing supports are selected from spherical joint rod ends and spherical joint bearings.
 13. A front-loading washing machine comprising, in combination: a frame; a drum supported within the frame; a basket within the drum and rotatable about a substantially horizontal central axis; a vibration isolation system including a plurality of vibration isolation assemblies mounted between the drum and the frame; and each vibration isolation assembly including an elastic member having opposed end portions and a central portion intermediate the end portions, a pair of opposed bearing supports supporting the elastic member at the elastic member end portions, and a connector secured to the central portion of the elastic member.
 14. The front-loading washing machine of claim 13, wherein the distance between the pair of opposed bearing supports is fixed based on the operating frequency of the washing machine.
 15. The front-loading washing machine of claim 14, wherein the length of the elastic member is selected to correspond to a fixed distance between the pair of opposed bearing supports.
 16. The front-loading washing machine of claim 13, wherein at least two of the elastic members are arranged in substantially parallel relationship.
 17. The front-loading washing machine of claim 13, wherein the elastic members are arranged in substantially parallel relationship to the horizontal central axis of the basket.
 18. The front-loading washing machine of claim 13, wherein the elastic members are arranged in substantially perpendicular relationship to the horizontal central axis of the basket.
 19. The front-loading washing machine of claim 13, wherein the distance between the pair of opposed bearing supports can be adjusted automatically based on an operational frequency of the washing machine.
 20. The front-loading washing machine of claim 13, further comprising an adjustment system for changing a distance between the pair of opposed bearing supports automatically based on an operational frequency of the washing machine.
 21. The front-loading washing machine of claim 13, further comprising a mechanism for adjusting the resonant frequency of the vibration isolation assembly.
 22. The front-loading washing machine of claim 21, wherein the adjustment mechanism changes a distance between a pair of opposed bearing supports.
 23. The front-loading washing machine of claim 21, wherein the adjustment mechanism comprises a continuously adjustable threaded rod that changes a distance between the opposed bearing supports.
 24. The front-loading washing machine of claim 21, wherein the adjustment mechanism comprises an automated system for monitoring the vibration frequency, comparing it to a standard value, and changing a distance between the opposed bearing supports in response to this comparison.
 25. The front-loading washing machine of claim 13, wherein the bearing supports are selected from spherical-joint rod ends and spherical joint bearings. 